Jump to content

Minimum AH for a starter battery


bill brown

Featured Posts

The battery you have is a dual purpose leisure type battery, which is not optimal for a starter battery. I would just go for a cheapo 110AH battery that most people use for starter batteries. Target price around £75. You could probably get away with something smaller but the cost saving won't be much so why bother. Often batteries are cheaper because they are a popular size, not because they are necessarily lower capacity. Make sure that whatever you get physically fits the space, and has the same type of terminals in the same orientation or at least that your existing leads will fit.

  • Greenie 1
  • Happy 1
Link to comment
Share on other sites

For a boat its wise to have a bigger start battery than a car with equivallent size engine. A boats needs more in reserve, for unlike a car it may not start as easily and probably won't be used anything like as frequently, especially in the winter as a car and may go long periods without being charged. You may have engine trouble whilst out on the water and may need to keep attempting starting whilst solving the problem.  Go at least to a 90a battery.

  • Greenie 2
Link to comment
Share on other sites

3 minutes ago, bizzard said:

For a boat its wise to have a bigger start battery than a car with equivallent size engine. A boats needs more in reserve, for unlike a car it may not start as easily and probably won't be used anything like as frequently, especially in the winter as a car and may go long periods without being charged. You may have engine trouble whilst out on the water and may need to keep attempting starting whilst solving the problem.  Go at least to a 90a battery.

Agreed - which Is why I suggested a car 2 litre+ diesel starter battery.

Turning over a 3 or 4 cylinder, 30hp 'little' boat engine should be easy compared to a 150PS 2.0 litre Ford Mondeo Diesel

Link to comment
Share on other sites

"Cold cranking amps" (CCA) is actually more significant for a battery just to start a boat diesel, than the Amp Hour capacity.  The two are not necessarily proportionally linked.

If you have a choice, go for the biggest CCA you can find, (and maybe the longest warranty), that doesn't significantly increase the price over the most basic.  As Nick says. somewhere around £75 is probably a reasonable target.  The resulting battery will probably not be less than 90Ah, but really that number isn't that significant, and going for (say) 110Ah, will not make it a "better" battery for the purposes of starting.

The advice to check not just it will fit, but also has the right terminal locations is good advice.  Some have positive and negative reversed, and leads may not reach as a consequence.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.